The present invention relates to a device for managing concurrent access as well as to an electronic device for its practice. Numerous applications such as the control of access of persons to localities or to installations, the control of automated processes along a production line, or the counting of products, use electronic devices known as contactless smart cards, tags or transponders. These devices, having no internal energy source, generally comprise at least one interfacial circuit coupled to an antenna and a programmable memory. They can moreover comprise a microprocessor and/or other electronic circuits adapted to process and transmit data contained in their memory. They are carried by their holder or by the object to be controlled and serve, as the case may be, as an access key to an installation, as an automatic access memory permitting the recovery or modification of prerecorded data, as a memory for variable data, such as prepayment units or as electronic tickets for controlling processes. These slave devices are adapted to be used with a master electronic device (emitter/reader) comprising electronic components necessary for the generation, shaping and emission of a modulated carrier bearing a coded signal.